(:*******************************************************:)
(: Test: K-SeqExprCast-271                               :)
(: Written by: Frans Englich                             :)
(: Date: 2007-11-22T11:31:21+01:00                       :)
(: Purpose: '--1999-12' is an invalid lexical representation for xs:gYearMonth. :)
(:*******************************************************:)
xs:gYearMonth("--1999-12")